Microplates are provided with a number of wells arranged in a matrix form (in array) which can contain a liquid, and 12 rows×8 columns (96 wells, row intervals and column intervals of 9 mm), 24 rows×16 columns (384 wells, row intervals and column intervals of 4.5 mm), 48 rows×32 columns (1536 wells, row intervals and column intervals of 2.25 mm) and the like are known, and tend to be standard internationally. Here, row intervals are the distance between the center of a well or the center line of the row in which the well is provided and the center of a neighboring well in the column direction or the center of the row along which the well is provided in the column direction, and the column intervals are the distance between the center of a well or the center line of the column in which the well is provided and the center of a neighboring well in the row direction or the center line of the column in which the well is provided in the row direction.
In the case where a simultaneous process is carried out using a number of types of liquids together using such a microplate, a dispenser apparatus having one nozzle head on which nozzles or nozzles for attachment of which the number is equal to the total number of wells in the microplate on which a dispenser tip is mounted is used, and all of the nozzles are inserted into the wells together for each microplate, where the same type or same amount of solutions or suspension liquids is sucked up and ejected, is used (Patent Document 1).
In the case where a sequence of processes is carried out by making a number of types of reagents react with a great number of test substances sampled from a great number of specimens to be processed in sequence, for example, the same number of microplates having wells of which the number is in accordance with the number of the specimens, which of microplate is the same as the number of steps or types of necessary reagents in the process, is prepared in order to contain reagent solutions, specimens and magnetic particle suspension liquids which are necessary for the process. The apparatus, which can make the magnetic particles adsorbed in the inner walls of the dispenser tips corresponding to the nozzles, is used so that magnetic particles are moved to the wells of a number of microplates in sequence, and a process for inducing reaction through suspension within the wells is carried out in sequence (Patent Documents 1 and 2).
Thus, when a great number of types of reagents are used for the process, the number of microplates is great, because one microplate is allocated for each type, and thus, the area for work becomes large. In addition, the distance over which the nozzle heads move corresponds to the distance over which the nozzle heads move when passing through all of the microplates of which the number of types of reagents required for the process, and therefore, when the number of microplates is great, the distance over which the nozzle heads move becomes great, and thus, there is a problem, such that there is a risk that it may not be possible to carry out the process quickly and efficiently.
In addition, in the case where the number of specimens is not so great and microplates of which the number corresponds to the number of specimens and the number of process steps are prepared, it is necessary to use a nozzle head where nozzles are aligned with row intervals and column intervals corresponding to the row intervals and column intervals of the wells arranged in the microplate, and thus, it is necessary to prepare other nozzle heads in accordance with the number of specimens.
Meanwhile, in the case where microplates with which cases of a great number of specimens can be dealt with are used when the number of specimens is small, and in the case where the liquids used in the process steps are aligned in one column or one row, and a nozzle head having nozzles aligned in one corresponding column or row is used, the maximum number of specimens is limited to the number in one row or column, and thus, in the case where the number of specimens exceeds the number in one row or column, there is a problem, such that there is a risk that it may be difficult to handle.
In particular, in the case where the number of specimens exceeds the number of nozzles in one row or column but the number is a divisor of the total number of the wells, and the divisor is a multiple of two numbers, there is a possibility that one microplate may be segmented so that the process can be completed without waste.
When the number of processes carried out in parallel is great, the number of wells in the microplates is great, making integration more necessary, and in addition, it is necessary to provide nozzles so as to be closer together, and therefore, the intervals between dispenser tips are small and the area occupied by the dispenser tips is small, and thus, there is a problem, such that there is a risk that the built-in function of the dispenser tips deteriorates.    [Patent Document 1] International Unexamined Patent Publication WO99/47267    [Patent Document 2] Japanese Patent No. 3115501